This is a GemFan 8x4.5R Reverse Rotation Carbon Filled Propeller. GemFan produces some of the finest Multi-Rotor propellers available. The High-Strength props are made from Nylon with Carbon Fiber fill for an extremely stiff blade that will not deform under load. These props are about 10 times stiffer than the standard GemFan Multi-Rotor props. "Reverse" rotation is counterclockwise.

The 8x4.5 props have a 5mm hole drilled in the hub, so they are ready to bolt on most 22mm motor prop adapters. Also included with the prop is a set of 3 adapter rings that step down the center hole of the prop to allow it fit on 3mm, 3.17mm or 4mm motor shafts. If you have a larger threaded shaft on your prop adapter, the center hole can be reamed out to 6mm or 1/4 inch as needed.